O2 sensor question

[Pgy]

Hi! I'm having some trouble with my Jeep Liberty 2003, 2.8 CRD, it's losing pulling power, not accelerating - mostly uphill. To describe the issue, even though i press the gas pedal, it slows down, rpms drop, it downshifts and then it gets a sudden "power burst" rpm go quickly up to 3k or around, picking up speed again.
I had this issue before some years ago, even though not as bad, the mechanic cleaned the 02 sensor, it seemed to do the trick. At the time i had a check engine light on, this time i don't.

I'm wondering if it could be the o2 sensor being faulty altogether? Also, If anyone can please confirm how many o2 sensors are fitted on this model, since i'm trying to find and buy them myself and not have the dealership order them for me (if indeed it's the same culprit). Any replacement recommendations?

Thank you all!

 

[KJowner]

There is no O2 sensor on the CRD, I'd guess he cleaned the MAP sensor, it's in the back of the inlet manifold.

 

[KJowner]

This is a picture of sensor location. Not my picture, I pinched it off Lost jeeps.

You must be registered for see images attach

 

[Pgy]

I changed the Map sensor already with a brand new one. That mechanic no longer works there so I’m just guessing now since I can’t remember what he did. Sorry for being vague

 

[Pgy]

Could it be the exhaust gas temperature sensor? I don’t know what can cause this power loss and they probably won’t find the cause unless there’s some error recorded or I request a specific checkup.

 

[KJowner]

Could it be the exhaust gas temperature sensor? I don’t know what can cause this power loss and they probably won’t find the cause unless there’s some error recorded or I request a specific checkup.

They don't have anything like that, it's an old simple setup, the fueling is controlled by boost pressure and throttle position, the only temperature probe is for the coolant. The picture above is from a later Jeep, ours don't even have a MAF fitted.
Did you change the MAP when this problem started or previously?
Check all the boost hoses and intercooler for splits and damage.
Probably worth putting a fresh fuel filter on too if it hasn't been done recently.

 

[Pgy]

Thanks for the info! I was confused because in the manual there is some sensors listed along the exhaust but discontinued from Mopar.
I changed the MAP before this started, about a year ago. This is been happening since May ( give or take) but gradually getting worse.

 

[KJowner]

Thanks for the info! I was confused because in the manual there is some sensors listed along the exhaust but discontinued from Mopar.
I changed the MAP before this started, about a year ago. This is been happening since May ( give or take) but gradually getting worse.

Probably the MAP again, did you get a genuine Bosch? It may clean up with a blast of carb cleaner.
Have you disconnected the EGR? That will make a massive difference to the MAP cleanliness.

 

[Pgy]

Yes, it’s Bosch. I’m not sure about the EGR, I didn’t disconnect it and I don’t think the mechanic did either. I have an appointment for an oil & filter change at the end of the month, hope that helps.

Also, I did the key diagnose test and I don’t get any codes. Not sure if that’s good or bad in this case.

 

[KJowner]

You won't get any codes if the MAP is dirty and possibly not if it's dying, as long as the reading from it is plausible the ecu will follow it, even if it is wrong. I think this is where you fault is.
Make sure all the filters are changed not just the oil filter.
The EGR is simple to bypass on the older Jeeps, the solenoid on the left side controls it, it'd vacuum operated, unplug the vacuum line, fold tape over the hose tail to completely block it and wrap a bit more round it then plug the hose back in, job done.